Rust in the kernel is not guaranteed to get stdlib. Running on bare metal is often done with `no_std`. Remembering how memory allocation in the kernel can happen in a multitude of ways, I'm not even sure the usual stdlib could be leveraged. Strings, for example, allocate memory implicitly.

That being said, apart from a good stdlib, I found Rust much easier than C due to a consistent type syntax, sum types, generics, traits, and the compiler hitting me on the head with lifetime errors.